ref: d53a7b09b6eb7ac6adce58f8239181dcaee54e6c dir: /sys/src/libc/port/_assert.c/
#include <u.h> #include <libc.h> void (*__assert)(char*); void _assert(char *s) { if(__assert) (*__assert)(s); fprint(2, "assert failed: %s\n", s); abort(); }